Pneumatic tool for upsetting hollow rivets



1%, 1949. B. e; CARLSON PNEUMATIC TOOL FOR UPSETTING HOLLOW RIVETS FiledJuly 9, 1947 INVENTOR. BERT G. CARLSON ATTORNEY Patented June 14, 1949UNITED STATES Parana o r Flor.

. tion of lOhio Application. July. 9,

I 2 Claims.

T'This invention -relates to improvements 'i-in meansfor-expanding-rivetsand-hasfor 'its'pri- 'marybbject to provide'amanuallybperable' blind rivet set, by the use of which the rivet maybe'insertedinan appropriate hole inthe'pieces to be rivetedtogether,therivet expanding-tool inserted "inthe'rivetand after simpleexpandingoperation be removed from the-rivet for subsequent expand- -ingoperations on other rivets.

With' this in mind, it is-proposed to; provide a --rivet-'-flaring-toolto include'a spindlewith a rule- -ber'-like sleeve and -a--'simple andeliective fliud pressure operated tool with manual push" button--control forretracting thespin'dlefor forcing the rubber sleeveto'uniformly expand the rivet. More specifically the inventioncontemplates-an improved fluid pressure operatedtool for-quick "massblind riveting operationto supplant the mechanical tools for' thesamepurpose disclosed in 'my United "Statespatents,"issued" to'-Bert G.

Carlson for Riveting apparatus, No; 2,370,776, March 6, 1945' and forBlindrivet hand toolyNo. 2;3'70;840,*March-'6, 1945.

With the -foregoing-and-' other objects in view,

the invention resides in the: combination of-parts and inthedetails-of-constructionhereinafter --set rorth'in the followingspecification and'ap- "pended claims, certain'embodiments thereof be-'ingillustrated 4 in the accompanying drawingsyin "which:

-'-Figure= 1 is a view indongitudinal sectiontaken through *myblindrivetingtool. andjshowing the --a'ssembly'-withtheun'flared rivet'thrustthrough two "plates to be'riveted'. together;

- Ffigure"2;;is a;similar view, 'showing'the rivet fiaredand the twopieces riveted together;

Figure 3 isaview in bottom :plan of the tool;

Figure 4 is an end view of the same; and i FigureSis a--viewin-longitudinal' section taken through a larger plug, spindle,rubber-sleevearld rivet.

Referring more particularly to the drawings, the device maycomprise'a'casing l with. a.bore -2tosilidably receive apiston 3iwith apackingring 1&4. In the'-bore"2 is removably screw-threaded a --plug5and removably' screw-threaded on plug 5 is a hand housing 6. Removablyand adjustably extending through plug 5 is a partially screw-threadedbolt 1 that may be held in adjusted position by a nut 8. Surroundingbolt I and central shank 9 of the piston is a compression coil springwhich bears on the stationary inner surface of plug to normally forcethe piston to the left against its seat in casing I.

On the left side of the piston the casing I is 1947;.Serial No 759,813

(Clfizl8 l9) m '2 re'duced'in cross seetion' at" I 1 vand hasa reduced*bore" llto receive a pistonro'd havinga reduced portion. l2 withappreciable radial clearance.be- "'tweenit andLborei II and .a .portion"l3 of, greater 5 cross-section so ,as' to..be snugly slidablein bore "1land provided with ajpacking ring I3. .A'keyaway 14 may. beprovidedin.rod portion l3; to re- "ceive' a'ball' l5 urged thereintoiby a set screwllfi the casing H to permitslidingibut prevent rotationv oflthe rod; Theforward end oftoasing'l l is interiorly screw-threaded to ..removablyreceive a screw plug [8. In the forwarduend. ofpiston "*rodl3 isremovably screwathreaded a bolt 19 "that'is slidable. in 'plug' l8 andterminates "at its ls forward 'endinan enlarged slottedhead 20.113011;"19 also extendsthrou'gh a removable sleeve'z l. of "rubben'or' thelike,and whose'normalacross-sectionmay be: equal to that ofbolthead" 20.

Tothe casing is. also, removably secured an .ingor'takepipe'in leadingfromasuitable source'of "pressure fluid to a horizontalrestrictedpassage .23 whichlatter leads to a larger vertical passage'124.' To the'bottom of the casing is removably.se- 'cured, a screw plugto retain.- against removal 25ithe"lip26.of a manuallyoperable pushbuttonTl of a springplunger' havingupper and lower valve "lands 28 and29 and an"intermedi'ate reduced portionl's it. Reduced portion '38 has asmall hole 31' -leadingfrom its annular. clearance in passage ""2t toavertic'al passage'32 Shownin'dotted lines to. extend upwardlythroughupper valve land 28. A. restricted. passagel33 providescommunication between passage 24....andl the, radial clearanceaboutrod'lzin bore 1 l. .'.A.compression.coil spring'3 l normally forcestherpushbutton and its valve lands downwardly into'their respectivenormal inoperative positions shown in Figure 1.

an .embodimentbf umyminventional have shown 'it ,asra'daptable. as .atool forraccomplishing "blind. riveting. f Thus when itis desired to op-..erate the v.tool for .this..purpose,;.a .sleeve-.2 laof rubber, orithe .like, of @a .desired given..length, is slipped, overt. bolt. .1 9and, thealatter slid. through plug laandthe-screw slot head manuallyturned ,to.screw. thebolt into..rod...l3 .to.-bring.one:.end.of sleeve2| into abutment with head 20 and the other end with the reducedprojection 36 of plug l8 without compressing sleeve 2| so that theoutside diameters of head 20, sleeve 2| and projection 36 areapproximately equal. Then the rivet 3'! is loosely placed around sleeve2| so that the permanently flared head 38 slides over projection 36 toabut the shoulder of the larger portion of plug 38. This assembly isthen manually thrust through registering openings in plates 39 and 40until the flared head 38 of the rivet abuts the outer, or visible,surface of plate 39 as it is too large to pass through the hole in theplate 39. The left side of plate 40 is the blind side and the problem isto effect an expansion of the rivet barrel on the blind side of theplate 40 so as to permanently rivet plates 39 and 40 together.

To accomplish this, push button 21 is pressed inwardly against theaction of spring 34 to the position shown in Figure 2. This brings uppervalve land 28 in a position to close the exhaust outlet 35 in the casingwhich communicates with passage 24. t also brings hole 3| and the radialclearance about the reduced portion 30 of the plunger into registry withrestricted passage 23. Thus, the pressure fluid flows through intakepipe 22, through passage 23, hole 3!, passage 32, passage 24, passage 33into the radial clearance about rod 12 in bore H. This forces the pistonto the right against the action of spring l until shank 9 abuts theadjustable length bolt 1 as a limit stop as viewed in Figure 2.

The result of this action is to draw bolt is and its enlarged head 20 tothe right to radially expand the sleeve 2! as well as the rivet barre1on the left, or blind side of plate 48. The radially expanded portion ofsleeve 2i is shown at 21E. This is a temporary deformation of the rubbersleeve but as it expands it forces the rivet 31 to be permanentlyexpanded as shown at 37E, both on the blind side of plate 40.

It follows that a release of normal pressure on the push button permitsspring 34 to return the push button and its valve lands to theirpositions shown in Figure I. In this position further access of pressurefluid from passage 23 to passage 24 is shut oil by the lower valve land29. Spring it in forcing the piston to the left to normal inoperativeposition exhausts the pressure in the chamber behind the piston throughthe exhaust port 35.

Figure shows a plug I8 similar to plug 58, but having a larger hole toreceive a larger rod IQ of greater length or diameter, or both, andhaving a larger head 20 to retain a sleev 2! of greater length or crosssection or both for retaining and expanding a larger blind rivet 31', orother articles to be expanded, which articles may be of greater lengthor cross-section, or both. This is to illustrate that the casing and theoperating mechanism is adapted to receive and flare any number of sizesof rivets. Moreover, the construction and operation of the fluidpressure operating mechanism and the simple and eifective manual pushbutton control make for efiicient mass operation.

I claim:

1. In a riveting tool for flaring the barrel portion of a hollow rivethaving a preformed flared head to rivet two pieces of material togetherand which tool includes a spindle for carrying a rivet, manuallycontrollable fluid pressure operated means for drawing the forward endof said spindle toward said means to radially flare said rivet barrelunderneath the second of said two pieces 4 of material and means forreturning said spindle to normal position upon release of said fluidpressure operated means, said pressure operated means comprising acasing, a piston slidably mounted in a cylinder in said casing andhaving a stem extending forwardly thereof, said stem having a reducedportion with clearance in said housing to form an annular passage incommuni-: cation with said cylinder on one side only of said piston, aninlet from a source of fluid pressure and an intermediate passagebetween said inlet and annular passage, an exhaust outlet leading fromsaid intermediate passage, a valve in said intermediate passage andmeans for normally maintaining said valve in position to opencommunication from said intermediate passage to said exhaust outlet andclose communication to said intermediate passage from said inlet, saidvalve being manually operable to close communication from saidintermediate passage to said exhaust outlet and open communication tosaid intermediate passage and to said cylinder from said inlet.

2. In a riveting tool for flaring the barrel portion of a hollow rivethaving a preformed flared head to rivet two pieces of material togetherand which tool includes a spindle for carrying a rivet, manuallycontrollable fluid pressure operated means for drawing the forward endof said spindle head toward said pieces to compress and radially flaresaid rivet barrel on the underside of said pieces and resilient meansfor returning said spindle to normal position upon release of said fluidpressure operated means, said pressure means comprising a casing, apiston slidably mounted in said casing and having a stem extendingforwardly thereof, said stem having an annular passage thereabout incommunication with said cylinder on one side only of said piston, aninlet from a source of fluid pressure and an intermediate passagebetween said inlet and annular passage, an exhaust outlet leading fromsaid intermediate passage, a valve in said intermediate passage andspring means for normally maintaining said valve in position to opencommunication between said annular passage and said exhaust and pistonspring means for normally forcing said piston to exhaust fluid from saidcylinder to said annular passage, a manual control for operating saidvalve against its spring means to open communication from said sourcethrough said intermediate and annular passages to said cylinder tooperate said piston against its spring means While closing said exhaustoutlet.

BERT G. CARLSON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,053,716 Huck Sept. 8, 19362,370,840 Carlson Mar. 6, 1945 2,384,347 Schulz Sept. 4, 1945

